Eid ul-Fitr is the earlier of the two official holidays celebrated within Islam.
Eid ul-Fitr is celebrated by Muslims worldwide because it marks the end of the month-long dawn-to-sunset fasting of Ramadan.
Eid ul-Fitr means "the feast of breaking the fast.
Sighting of the crescent Moon marks the beginning of the Islamic lunar month.
An Islamic month can have either 29 or 30 days depending on when the new crescent Moon is first visible.
According to an article by Islamic Relief Island, the Islamic calendar operates on the lunar cycle.
All significant days in the Islamic calendar appear to shift forward approximately 11 days each year
